a. Field of the Invention
The present invention relates to antennas for radio frequency devices, and in particular, to such antennas for hand-held data terminals which utilize radio frequency transceivers.
b. Problems in the Art
Hand-held, easily portable data terminals are becoming increasingly popular. Similarly, wireless communication, for example, via radio frequency transmissions, is utilized with many of these types of devices. Such communication allows easy and advantageous communication of information from a small portable terminal to a larger remotely positioned computer or other device and, conversely, allows information from the remote terminal or base to be instantaneously conveyed to a remote hand-held terminal.
Radio communication requires a radiating element or antenna. Conventionally, antennas for hand-held terminals take the form of a small helically wound stub antenna. Such antennas provide an adequate range and reception and are preferred because their small size matches the small, hand-held size of the terminal.
Problems and deficiencies do exist with such stub antennas, however. They generally extend from the terminal housing and therefore are susceptible to contact and breakage. Also, the mere fact that they extend the outer dimensions of the terminal conflicts with the attempt to make terminals as small as possible. The mere physical presence of the stub antenna also limits placement of these devices in cooperating devices such as recharging cradles, data download mounts, and other accessories.
It would therefore be beneficial if the need for an external, outwardly extending stub-type antenna were eliminated. It is therefore a primary object of the present invention to provide a means which solves the problems and eliminates deficiencies in the art.
A further object of the present invention is to provide a means which provides an antenna which performs generally as well or better than a conventional helical stub antenna, but eliminates the antenna from having to extend outwardly from the terminal container and be subject to damage or breakage.
A further object of the present invention is to provide a means as above described which conforms generally closely to the housing of the hand-held terminal or is entirely internally contained within the hand-held terminal.
Another object of the present invention is to provide a means as above described which does not physically cause interference between the primary perimeter of the hand-held terminal and such things as recharging or data communications connection cradles.
A still further object of the present invention is to provide a means as above described which utilizes materials and positioning which renders the antenna generally omni-directional in performance, while shielding it from direct physical contact.
Another object of the present invention is to provide a means as above described which can be placed to minimally impact upon size or placement of components, connections, and ports with respect to the housing and terminal and its normal operation.
These and other objects, features, and advantages of the present invention will become more apparent with reference to the accompanying specification and claims.